Damper regulator



Aug. 13, 1940. P. SPENCE 2,211,300

DAMPER REGULATOR Filed May 12, 1936 3 Sheets-Sheet l INVENTOR PAUL 5511 SPE/VCE ATTORNEYS -Aug. 13, 1940. 'P. SPENCE 2,211,300

DAMPER REGULATOR Filed May 12, 1936 s Sheets-Sheet 2 TOR INVEN PAULSE/V SPE/VCE ATTORNEYS Aug. 13, 1940. P. SPENCE DAMPER REGULATOR Filed May 12, 1956 3 Sheets-Sheet 3 INVENTOR PAUL SEN SPE/VCE firm-1% 1 4 A TORNEYS Patented Aug. 13, 1940 UNITED STATES QF'FIC Application May 12, rear, Serial no. meat 2 Claims.

My invention relates to a damper regulator or the like, and this application is a continuation in part of my co-pending application, Serial No. 538,430, nledMay 19, 1931, now Patent No. 2,8 1059 of May 12, 1936.-

llt is the general object of my invention toprovide an improved damper regulator, or the like, embodying an improved thermostatic or other control.

It is another'object to provide a damper regu= lator embodying a loading means for normally urging the damper toward one extreme of its movement and means controlled thermostatically or otherwise for varying the efiective loading of said loading means.

It is another object to provide novel and improved features in a damper regulator, with a view to greater accuracy in operation and simplicity of construction.

Other objects and various features of invention will be hereinafter pointed out or will hecome apparent to those skilled in the art.

In the drawings which show, for illustrative purposes only, preferred forms of the invention- Fig. 1' is a view'partly in elevation and partly in section of a boiler and damper regulator, illusin which the damper regulator loading variation is manual but in. accordance with automatically indicated temperature at a. selected point.

, My improved damper regulator includes means for varying the loading of the means regulating or actuating the damper. In-that form of the invention illustrated in Fig-1 and as to which form this application is a division of my aforesaid co-pending application, I represents generally a thermostat. -In the form shown in the drawings thethermostat is a. pneumatic thermostat having a body 2, a, flexible diaphragm 3 and a diaphragm chamber 4. A' thermostat bulb 5 is connected by means of a. pipe shown to the diaphragm chamber 4. The parts 4, 5 and 6 together form a. closed chamber in which is confined a quantity of vapor tension element which expands as its temperature increases. The ther= mostat bulb i will ordinarily be placed where it is exposed tothe temperature of the outside air, but it may be placed in any other location, 5 the temperature at which is to control the valve. Attached to the body 2 are one or more spring rods lli, which are surrounded by spiral springs 8-8, which are supported by adjusting nuts 9-9, which are threaded on the rods ll'. A lever 1 ill, is operated in one direction'by the pressure on the diaphragm and in the opposite direction by the springs Supported by the springs 8-43 is a spring yoke M, and enacting with the diaphragm 3 is a dish it. A lever yoke it is held between the spring yoke M and the disk l2 and has an opening therein through which the lever it) passes. The lever ill is pivoted to the body 2 in any convenient manner as by a pin M which passes through holes in the body 2 and in the lever it. A number of these holes are provided to adjust the leverage. The body 2 provides a positive stop for thediaphragm The springs t-8 may therefore be placed under an initial tension by means of the adjusting nuts 9-9. The thermostat i controls the loading of a fluid pressure actuated means which is in turn connected to and actuates the damper.

In Fig. 1, it represents a steam boiler which is equipped with a valve or damper for regulating the flow of air to the furnace or the flow of gases from the furnace-to the chimney. In the form shown 49 represents the body of such a valve or damper and so represents the valve head or damper proper. The valve as shown is positioned so as to regulate the flow of air to the furnace. The valve head 50 is pivoted at 5i. Fixedly attached to the valve head 5% is a weighted arm 52 which normally tends to hold the valve open. 53 is a connection between the arm 52 and a lever 54 which is pivoted at 55. The lever 54 is actuated in a direction to close the valve by a fluid pressure operated actuator 56 which is operated by steam from the boiler I8. 51 is a weight which is adjustable longitudinally of the arm 54. 2! is a connection which connects the thermostat to the lever 54.

It willbe seen that as the temperature to which the thermostat bulb 5 is exposed is increased, the left hand end of the lever Ill will be moved upward, thereby exerting a. force on the. lever 54 which will tend to close the valve.

The operation of the device is as follows: 7

Let us suppose that it is desired to maintain a steam pressure in the boiler 48 of lbs. per

square inch when the temperature of the outside air is F. and that it is desired to maintain a pressure of 3 lbs. per square inch when the temperature of the outside air is 50 F. The setting ofthe weight 5'! will be adjusted so as to permit the valve to close when the pressure in the boiler reaches a pressure of lbs. per square inch. The tension of the thermostat springs 8-8 will be adjusted so as to maintain a pressure of 3 lbs. per square inch at .50" F. The length of the connection 2i will be adjusted so that there will be no force transmitted by the connection when the air temperaturesis Of F.-

With this arrangementit is apparent that'when the temperature of the outside air is 0 1'. the weight 5! will move the lever 56 downward against the pressure exerted by the pressure actuated means 56, so as to permit the valve to open widely until the pressure in the boiler reaches 10 lbs. per square inch. On the other hand, when the temperature of the air is greater than 0 F. the thermostat which is connected to the connection 2! will exert an upward pull on the lever 55, thereby permitting the valve to be closed by a lesser pressure in the pressure actuated means 55. When thetemperature of the air reaches 50". F; the upward pull of the thermostat on the arm 56 will ofi'set the eiiect of the weight 51 to such an extent that a pressure of 3 lbs. per square inch in the pressure actuated means 56 will be sufllcient to close the valve.

In the form shown in: general in Figs. 2 and 3 the damper is actuated or controlled directly in its movements by a motor, which may be operated by any suitable source of pressure fluid,-

ing the loading on the pressure actuated means in accordance with a control condition, as the temperature at a control point, for instance at the outside of a building, and also, if desired, in

accordance with wind velocity.

. In Fig. 2 50 indicates a boiler having a stack 6i and a damper 52. The damper may be urged toward closed position, as by means of a weight 63, as will be understood. The position of the damper 62 is controlled by what may be termed the damper regulator proper or motor 66. The motor shown comprises a cylinder as having a piston 56 movable therein. The piston rod 6'! projects through a stuiiing box in one of the cylinder heads and isattached by means of a flexible connection 68 to an arm on the damper 62, so that when the piston 66 is moved upwardly the damper will close and, conversely, when the piston 66 is moved downwardly in the cylinder, the damper 62 will open.

The motor 64 is controlled by a pilot valve 69, which comprises a valve casing Ill having pressure connections ll'|2 to opposite ends of the cylinder 65. A fluid pressure inlet pipe 13 opens into the casing Hi at a point between the inlet openings of the-connections '|l12 and a waste or discharge outlet pipe 14, is connected to the casing and communicates with the various passages. valve 15'. Thus, when the spool valve 15 is lowered slightly from the position shown in Fig. 3,.

The passages are controlled by a spool neath the piston 86 for raising the same.' At the same time fluid above the piston may pass out the pipe 12 and into the waste pipe 14. On the other hand, when the spool valve is raised from the position shown in Fig. 3, pressure fluid from pipe 13 may pass through the spool valve and through the pipe 12- to the cylinder above the piston, while at the same time fluid below the piston 88 may discharge through pipe H and into the space below the spool valve and through a passage (not shown) into the waste pipe M. Thus, by movement of the spool valve lii either up or down, the actuation oi the piston 66 is efiected.

The position of the spool valve is controlled by several factors, including the steam pressure.

As illustrated, a fluid pressure means, such as a' diaphragm casing It, is mounted on a bracket on the motor 84. Fluid pressure actuated means may include a diaphragm I1 in the casing and from the diaphragm chamber 18 a pressure connection 79 leads in this instance to the steam space oi the boiler 60 so that boiler pressure is always on the upper side of the diaphragm. Either connected to the diaphragm or urged into engagement therewith is a stem 89 which, at the lower end, is connected to a yoke 8i carrying one part-of a pivotal connection, while a lever 32 embraced by the yoke carries the other part of a pivotal connection. The lever 82 is hung in a swinging bifurcated bracket 83 from the casing l6 and the lever 82 is pivoted in the swing ing bracket 83 by improved means which will be later described. The lever to the left of the pivots is pivotally connected as by means of a pin and slot connection 85 to the piston rod 65 of the spool valve 75, so that as the lever 82 oscillates, for example under the influence oi the steam pressure in the diaphragm chamber 58, the spool valve will be moved up or down so as to effect movement of the piston 86 and consequent changing of the damper setting. A spring 85 connects the piston'rod 61 to the left hand end of the lever 82, so that as the pistonBG moves up wardly, tending to close the damper, the spring 86 is tensioned, thus urging the lever 82 about its pivotal connection 83 and tending to raise the spool valve 75 and shift the valve 15,.so as to tend to close the damper. Thus very close regulation of the damper position may be maintained. An

adjustable counterweight 81 is secured on the shall describe improved pivot means for the lever;

82 making for relatively frictionless'pivotal movement of the lever, with consequent greater accuracy in' maintenance of steam pressures. As shown in Figs 4 and 5, the hanging pivot link 83 is pivoted as by means of a through pin 88 to a pair oi ears 80 on the diaphragm casing 16. The

link 83 is bifurcated and in each of the arms are mounted pins 89 which pins extend inwardly toward each other and up quite closely to'the sides of the lever 82 so as to act as guides for the latter. The lever itself carries a square pin 90 projecting from opposite sides thereof, and one edge of the square pin. which I term a kniie edge, rides in V-grooves 0I-9I in th: inwardly projecting pins 80-40. By the means described, the knife edge pivotal connection is almost frictionless and the slightest unbalanclng of the lever 82 serves to move the same with consequent proper regulation of the pressure. Furthermore, the pivotal connection between the lever 8| and the yoke 02 may be of the same form as that shown in Figs. 4 and 5, except that the pin carried by the lever acts upwardly on the V-grooves of the pins carried by the yoke 8i, instead of downwardly, as shown in Figs. 4 and 5. Another feature making for extreme ease of oscillation'of the lever 82 resides in the elimination of a tight stufling box on the pilot valve casing 10. In place of the usual stuffing box I provide a relatively loose fitting bushing 02 about the valve stem 05, near the top, and a second relatively loose fitting bushing 90 about the valve stem 05 at a point just above the chamber leading to the discharge pipe Id. In other words, I provide instead of a tight stufiing box a joint which is capable of substantial leakage, thus making for very free sliding movement of the valve stem 05. Any fluid which might otherwise leak out through the upper bushing 02 is discharged-through a waste pipe 0d between the two bushings, and since the capacity of the waste pipe 04 is so much greater than the space between the loose fitting bushing 92 and the stem 85, there is no danger of leakage past the bushing '92.

By the means described, it is possible to maintain steam pressures within exceedingly close limits; that is to say, for ordinary low pressure house heating boilers where pressures of only a pound or two are generally maintained, my damper regulator will regulate such steam pressures within limits of an once or less.

I have provided improved means for varying the normal loading on the damper regulator, which means varies such loading in accordance with one or more control factors, such as temperature, at a control point or at the outside of a building, and wind velocity or other factors which can act as control factors for the damper, thus causing a steam pressure to be maintained commensurate with weather conditions. In the form illustrated, I employ a thermostat W0 which actuates a blade IOI contacting with a resistance i02 and constituting what I term a control potentiometer. The blade is connected to a wire R and one side of the resistance H02 is connected to a wire W, while the opposite side is connected to a wire B. These wires are connected to the usual line wires, preferably through a transformer I03, as shown. The wires W, B and R lead through a panel hoard, designated generally I04, to solenoid coils I05 and a balancing potentiometer coil I06. One or the other of the coils I05 serves to alternately move the core I01, controlling a switch blade I08, which, depending upon its position, makes contact to energize one or the other of the rotary motors I09 driving shaft H0. Thus, energizing one of the motors I00 will serve to rotate the shaft I I0 in one direction, while energizing the other will serve to rotate the shaft H0 in the opposite direction. On the shaft H0 is a blade III electrically connected to the wire R. Now, suppose the outside temperature rises. The thermostat I00 will move the blade IOI toward the left so as to reduce the resistance in the wire W. Such reduction in resistance in the wire W unbal-ances the coils I05 and causes the switch I08 to move to the left so as to energize the left-hand motor I09 and thus rotate the shaft in the direction of the left-hand arrow. Such rotation of the shaft, which may be called in the closing direction, will rotate the blade III of the balancing potentiometer-so as to increase the resistance in the lower half of the balancing potentiometer coil I06 and when the resistances in the W and 18 lines have become balanced, the core IIO'I will again be moved to its mld-positionand the contact blade I00 will break its contact with the motor H09 and the motor will stop.

During the rotation of the shaft M0 in the closing direction through means which I will now describe, the loading on the lever 82 will be de creased and, as heretofore stated, decreasing the loading on the lever will cause the damper 02 to be moved toward closed position and the steam pressure thus reduced. The loading means illustrated comprises a loading chain i i2 connected to the lever 82 and through a flexible connection to a generally spirally formed cam wind up member lit. Rotation of the shaft iid in the socalled closing direction winds up the end of the loading chain M2, thus reducing the loading on the lever 02. Now, should the outside temperature drop. the reverse action of that described would taire place. and the motor shaft M0 would be rotated in the direction of the right hand arrow, that is. in the so-called opening direction, so as to increase the loading on the lever 82 and thus open the damper so as to increase the steam pressure. While with the type of thermostat disclosed. equal temperature increments will move the blade 60E by substantially equal increments, it should be observed that because of the generally spiral or cam formation of the wind up device Iiiii, the lever 82 will not be loaded by equal increments.

In addition to the temperature control, I may also provide a wind control. Generally spealring, temperature conditions being constant, an increase in wind velocity requires an increase in steam pressure. I have illustrated a conventional type of anemometer lid with fiy ball governor lid. The fly ball governor controls blades iil inthe W, B and R lines so that upon an increase in wind velocity (thus requiring a greater steam pressure). the resistance of the B line is reduced and the resistance of the W line is increased. As heretofore described. the effect oi such resistance variations in the W and B lines will cause the shaft M0 to be rotated in the socalled opening direction so as to increase the loading on the lever 02 and thus cause an increase in steam pressure.

Tn dd t o e controls'noted. wh ch may of course be used together or independently. I may employ a high limit room thermostat H0 which, when the high temperature limit is reached, will cause the W and R lines to be short circuited by closing of the contacts between those lines through the lines H0. ing of the W and R lines will cause the motor to rotate the shaft H0 in the closing direction so as to unload the lever 02 and thus cause the damper to be moved toward closed position.

By means of the control panel I04, the loading of the damper regulator may be completely taken off of automatic control and put under manual control by means of the manual blade I20 and switch I20". With the switch I20 in the position shown the automatic control is as heretofore described. With the switch I20 in its other circuit position, that is, when engaging the contact I20", the automatic control will be inoper- Such short circuit- I28 is on manual control.

resistance I2II' the dlflerence in resistance between the W and B lines relatively to the R line. will be varied and the loading motor will be actuated to load or unload the damper regulator in accordance with the position of the blade I20. Protective fixed resistances I04, I64" are in the W and B lines and are efiective when the switch The variable resistances M M 14 in the B, R and W lines also act as protective resistances and are princlp'ally for adjustmentof resistances in the three lines. Various features in connection with the temperature and wind velocity devices have been disclosed and claimed in my co-pending application, Serial No. 47,778, filed November 1, 1935.

Instead of the purely automatic devices for controlling the loading of the damper regulator in accordance with, say, outside temperature, I may provide manual means for such control, together with automatic means, for indicating the desirability of load variation and the extent of such variation. In Fig, 6 I have shown diagrammatically such a manual device. As there shown, the thermostat I39 actuates a blade I 3| in accordance with outside temperatures. The blade ISI contacts a resistance I32 similar to the resistance heretofore described. The W, B and R lines, connected to the resistances I32 and the blade I3I, serve to control the coils I33 so that the contact member I36 will be moved either to the right or the left. For example, upon a rise in temperature, the blade ISI will be moved so as to reduce the resistance in the W line and the contact member 938 will be moved toward the right so as to close the contact through point I35 and thus energize the signal I35, which may be a buzzer, a red light, or other desirable device indicating a rise in the outside temperature. Conversely, a drop in the outside temperature will cause the contact ass to close the circuit through contact point I3! so as to energize the signal I 38 which may be a buzzer, green light, or other device, to indicate a falling temperature. Thus, immediately upon a change of temperature condition, which should be compensated for by variation in steam pressure, the operator is given a definite signal. In circuit with theresistance I32, I have a second resistance I39, which is contacted by a manually movable regulating blade ltd. When the signal is given either by the device I35 or I33, the operator manually moves theblade Mt so as to energize the resistance in the W and B lines and thus the contact blade I3 I' will be moved to its open circuit position and the signal will cease. Such manual movement of the blade Hill is employed for controlling the loading on the damper regulator. In the form shown, the blade I40 is on a shaft I which carries a blade I42 contacting a resistance I43. The blade I42 is connected to an R. line while the opposite ends of the resistance I43 are connected to W and B lines the same as heretofore described in connection with Fig. 2. These lines, connected to the blade I42 and resistance I43 may be substituted for the corresponding lines in a control system such as shown in Fig. 2; that is to say, the resistance I43 may take the place of the resistance I02 and the blade I42 may take the place of the blade Id! of Fig. 2 so that all of the variations defined in connection.

with Fig. 2 may be efiected by the means disclosed in Fig. 6, exceptthat instead of having the blade I42 move automatically in accordance with temperature changes, the latter is moved manually in accordance with the change indicated by the signal devices I3E- I38. When the blade I42 has been moved (concurrently with blade I40) to the desired extent, as stated the. signal will be disconnected and the motor will have moved the damper regulating loading device to the desired extent and in the desired direction.

While the invention has been described in con- 'siderable detail and modifications illustrated, it

one sideof the pivot point, loading means for said lever at the opposite side of the pivot point, a connection between said pilot valve and said lever and located between the pivot point and said spring, and a connection between said diaphragm and said lever and located at a point between said pilot valve connection and the pivot point, and a pressure connection to said diaphragm from a boiler.

2. In a damper regulator, a fluid pressure actuated motor for moving a damper, a pilot valve for controlling the supply of pressure fluid to said motor for moving the same in at least one direction, fluid pressure actuated means for urging said pilot valve in one direction, loading means for said pilot valve, said loading means including a chain cooperating with said pilot valve, a rotary motor, a generally spiral form. of cam rotatable by said motor, and means for connecting said chain to said generally spiral form of cam, whereby upon equal increments of rotation of said rotary motor and cam the latter will pay out or wind up unequal increments of chain.

' PAUISEN SPENCE. 

